Electroresponsive device



Oct. 22, 1940. w ZENNER 2,219,157

ELECTRORESPONSIVE DEVICE Original Filed Dec. 31. 1936 Zinmntor WALTER J. ZENNER Jyf Gttorneg Patented Oct. 22, 1940 UNITED STATES ELECTRORESPONSIVE DEVICE Walter J. Zenner, Des Plaines,

Teletype Corporation, tion of Delaware 11]., assignor to Chicago, 111., a corpora- Original application December 31, 1936, Serial No.

118,526. Divided and this application Novem- 3 ber15,1937,SerlalNo.174,555

6 Claims.

This invention relates to printing telegraph apparatus, and particularly to a selector mechanism for the control of such apparatus.

This application is a division of application Serial No. 118,526, filed December 31, 1936, which matured into patent 2,170,316 granted August 22, 1939 to W. J. Zenner.

An object of the invention is to provide a selfaligning mounting for the armature of a selector magnet.

Briefly, the invention contemplates a rockably mounted armature lever which carries the selector magnet armature in spaced and yieldable relation to said lever, so that the armature may rock about its mounting and come into engagement with the pole faces of the-magnet without requiring that critical adjustment of the armature lever that is essential to a rigidly mounted armature.

For a full and complete understanding of the invention; and of the manner in which it may be practiced, reference may be had to the followlng detailed description, taken in connection with the accompanying drawing in which,

Fig. 1 is a top plan view partly broken away, showing a selector mechanism embodying the several features of the invention;

Fig.2 is an elevational view of the selector mechanism shown in Fig. 1;

Fig. 3 is a sectional view, taken on the line 33 of Fig. 1; and

Fig. 4 is a detailed perspective view, partly exploded and partly broken .away, showing the salient features of the selector mechanism of Fig. 1.

Referring now to the drawing, in which corresponding reference characters represent identical parts throughout the several views, and particularly to Figs. 1 and 2, reference numeral l designates a mounting plate which serves as the foundation of the selector mechanism. Adjacent to one end, mounting plate I ll has secured thereto, by means of clamping screws l I, a selector magnet assembly indicated generally by the reference numeral I2.

Selector magnet assembly l2 includes a bracket l3 through clearance holes in which pass the clamping screws ll. Bracket I3 is movable through an arc, for purposes oi. adjustment, about an integral cylindrical projection H which is disposed in a similarly shaped and correspondingly dimensioned aperture in plate Ill, and pivotal movement is efiected by rotation of,a screw It, the shank of which threadedly engages bracket l3 at the opposite end to that which carries pivot projection l4. Screw i6 is provided with slotted head in spaced relation to head I! with flange l8. Plate ID has fixed thereto and extending up- 6 wardly therefrom stud I 9, the upper end of which terminates between screw head I! and flange l8. Stud l9 being thus confined between screw head I! and flange l8, screw 16 is incapable of axial movement, and when it is rotated, bracket I3 is 10 moved angularly about the axis of projection H. Screw head I1 is provided with radially extending 'sockets 2| in the periphery thereof, so that when the selector mechanism is installed in such positlon that access to the.slot by screw driver cannot be had, screw 16 may be rotated by a bar-shaped implement applied to successive ones of the sockets 2|, in the manner in which capstans are rotated.

Bracket l3 has magnet core 22 secured thereto by means of screws 23. Core 22 has two arms, each of which supports an electrical winding 24 and terminates in a pole face 26.

An armature lever assembly 3| comprises a bell crank lever having arms 32 and 33. Arms 32 and g5 33 may be integral, and adjacent to the point of intersection of these arms is secured, by means of-clamping block and screws or rivets 36, a thin, flat strip of flexible material, such as spring steel, which is intended to serve as a mounting hinge for the armature lever, and is identified by the reference numeral 31. Spring hinge 31 extends free of armature lever arm 32 and clamping block 34, and the free portion is rigidly secured to bracket l3 by.; -rr ieanoi clamping block 35 38 and clamping screws 39. Preferably, arm 32 of armature lever 3| overlaps bracket l3 slightly at the point of clamping of spring hinge 31 in order that endwise movement of arm 33 of the armature lever, due to flexing of spring hinge 31, may be prevented. Fig. 4 affords an enlarged detailed view of the mounting of the armature lever on its spring hinge.

At its free end, armature lever arm 32 supports a floatingly mounted selector magnet armature II in a manner clearlyindicated in Fig. 4. Referring to that figure, it will be noted that armature lever arm 32 is provided with an aperture 42 which is adapted to receive the shank of a headed screw 43. Preferably, aperture 42 is of such diameter, by comparison with the shank of screw 43, as to be a clearance hole therefor, so that the shank of screw 43 may be capable of shifting about within aperture 42. Lever arm 32 has anchoring pins 44 positioned on opposite I1, and

sides of aperture 42 extending above the surface of lever arm 32 which is presentedtoward'the pole face 26 of the selector magnet. A flexible spring member 46 has apertures 41 adapted to fit over pins 44, and a central. aperture 48 adapted to be entered by screw 43. Spring member-46 has arms 49 extending clear-of armature lever arm 32 in opposite directions, and arms 49 are preferably bent toward pole faces 26. Armature member M has a threaded aperture 5|,which is threadeclly engaged by screw 43, and also has grooves 52 in which the outer ends of arms 49 of spring member 46 are seated. Armature 4| is thus supported on armature lever arm 32 by screw 43 and is maintained in spaced relation to the armature lever arm by spring member 46. A spacer 50 limits movement of armature 4| in the direction of the axis of screw 43. Pins 44 prevent spring member 46 from rotating on screw 43, and grooves 52 confine armature H to an upright position. The armature is free to rock in order to align itself with the pole faces 26 when the armature is presented to the pole faces, and a critical alignment of armature lever arm 32, with' respect to pole faces 26, is not required.

Arm 33 of the armature lever includes cam follower portion 56 arranged to engage an armature cam 51 included in cam assembly 58 carried by a power-driven shaft 59. At its outer end, lever arm 33 is engaged by one end of a .tension spring 6|, the other end of which engages a bracket arm 62 adjustably mounted by means f split mounting block 63 and clamping screw 64 to post 66 carried by mounting plate I0. Ann 33 of the armature lever has secured thereto a bracket 61 which has depending arms 68 and 69 positioned on opposite sides of lever arm 33 to serve as spring supports in a manner which will be described hereinafter.

In order that the previously mentioned cam assembly 58 may be disposed in a position to present the several cams included therein in operative alignment with levers they are arranged to control, mounting plate I0 is provided with aperture 1| through which shaft 59, which may be driven from any suitable source, such as an electric motor, may project. Shaft 59 has secured thereto spaced discs 12. Between discs 12, cam assembly 58 is mounted on shaft 59 and has at its opposite ends discs 13 fixed to the cam assembly. A friction disc 14, of any suitable resilient material such as felt, is mounted on shaft 59 between each of the discs'12 and the adjacent disc 13. .E'he assembly comprising discs 12, 13, and 14 constitutes a friction clutch through the medium of which rotation may be imparted to cam assembly 58 by shaft 59. In addition to armature cam 51, cam assembly 58 includes a locking cam 16 having a plurality of apices, and a plurality of cam projections 11 arranged helically around the assembly. The functions of cam 16 and cam projections will be set forth hereinafter.

A selector lever assembly 8] includes a mounting bracket 82 adjustably secured to mounting plate I6 in a manner fully described in Patent No. 2,203,300, granted June 4, 1940, to E. W. F. Hanke. Itemay be stated, however, with reference tothe mounting of bracket 82, that screws 83 are clamping screws extending through clearance hotes in bracket 82, and screws 84 and 86 have eccentric heads provided for the purpose of adjusting bracket 82. Selector lever 81 is rockably mounted upon bracket 82 by means of a spring hinge 88- similar to spring hinge 31. Spring hinge 88 is clamped to bracket 82 by means of -'92 and clamping screws 83.

clamping block 89 and clamping screws 9|, and

. described in the above identified patent of E. W.

F. Hanke. Selector lever 81 may also have at its free end locking lug 91 which is adapted to be blocked under certain conditions by locking blade 98 of locking bell crank lever 99. This bell crank.

has one arm engaging cam 16 and is adapted to be rocked clockwise each time one of the apices of the cam is presented to the bell crank.

Selector lever 81 is provided with depending arms II and I02, which, as shown in detail in Figs. 3 and 4, cooperate with depending arms 68 and 69 of bracket 61 secured to armature lever arm 33 to support centering springs by means of which selector lever 81 is caused to follow the selective conditions established in the armature lever. Thus, tension spring I03 extends between arms 68 and I02, and tension spring I04 extends between arms 69 and IN. The tension of springs I03 and I04 is such that selector lever 81 tends to be positioned midway between arms 68 and 69 of armature lever arm 33.

Selector lever 81 is provided at its free end with spaced depending arms I06 which are effective to control the several elements of a sword and T lever selector mechanism designated generally by the reference numeral I01. Sword and T-lever selector I01 comprise a plurality of thin, fiat selector fingers or sword levers III and an equal number of T-levers I I2 individually aligned with the selector fingers III. The selector fingers III are individually supported by spacer plates II3 which also separate the T-levers H2 and which are mounted on studs II4 carried by mounting plate I0. Each of the selector fingers III has at'its left-hand end, as viewed in Fig. 1, a disc-like portion II6 which is fitted into a correspondingly 'shaped aperture in a selector finger operating bell crank lever II1 pivotally mounted on a pivot pin I I8. Each of the bell crank levers H1 is arranged to be rocked counterclockwise by one of the cam projections 11 included in selector cam assembly 58. Adjacent to the disc-like portion H6, each selector finger or sword lever III is provided with oppositely extending arms II9 which terminate in abutments I2I.

T-levers II2 are rotatably mounted upon pivot pin I22 carried by mounting plate I0, and each of the levers is provided with an arm I23. Arm I23 terminates in disc-like portion I24. T-levers H2 are intended to be articulated by means of the disc-like portions I24 to code bars, code discs, or other permutation code elements (not shown), as disclosed in Patent No. 1,745,633, granted February 4, 1930, to S. Morton et al. Selector lever 81 is adapted to be rocked, in a manner which will be described later, through an arc sufiicient to bring one or the other of its arms I06 into the path of one or the other of abutments I2I of selector fingers III, as those fingers are reciprocated 'leftwardly by the associated bell crank levers H1, and such angular'movement of selector lever 81 is suflicient to bring locking log 91 from one side to the other of locking blade 98 carried by locking bell crank 99. Continued reciprocation of a selector finger III after one of its abutments I2I has engaged one of the depending arms I06 of selector lever 81 causes the selector finger to move angularly about the center of its disc-like portion I I6 to bring its free end into engagement with its associated T-lever H2 at the opposite sideof the pivotal mounting -I 22 thereof. The angular movement or selector fingers III islimited by stop pins-I26 carried by mounting plate I0.

The rot'ati'onpf selector cam assembly 58 by shaft 68 is controlled by a stop gate I3I which is periodically presenteddn blocking condition in the path of a stop arm I32 rigidly secured to selector cam assembly 68.; Stop gate I3I is pivotally supported by stud I33 carried by plate I34 whichis pivoted by means of pivot screw I36 to plate I31 rigidly secured on posts 66. An arm |38 mounted on pivot screw I36 above plate I31 has extending therethrough the shank of a knurled-headed screw I38 which threadedly engages stop gate mounting plate I34. Plate I34 may be adjusted pivotally about pivot screw I36 to vary the location of stop gate I3I and may be clamped in any desired position oi adjustment by drawing plate I34 and arm I38 into clamping engagement with plate I31 by means of screw I39.

Stop gate I3I has an arm I which is presented in the pathoi cam assembly stop arm I32 when the stop gate is in itsextreme clockwise position, and a spring (not shown) biases stop gate I3I so that it tends to rotate into its extreme clockwise position. The stopgate may be locked in the position to which it tends to be rotated by the engagement of a shouldered portion of latch lever I42 with arm I43 of the stop gate. Lever l42*ls mounted on stop gate mounting plate I34 by means of pivot I44 and is normally urged into locking engagement with arm I43 of stop gate I4| by'conipression spring I46.

A bell crank" I41 pivotallimounted on bracket 'I48 carried by plate I31 has one arm I48 engaging stop gate locking lever I42'at the end opposite to the shouldered portion which engages stop gate I33, andhas another arm II, the free end of which is disposed in a notch in the free end of armature lever-3l (Fig. 1).

In the rest condition of a selector mechanism, such as the one shown herein, when the mechanism is prepared to respond to incoming telegraph signals, but signals are not on the telegraph line, a continuous energizing currentis applied to winding 24 of selector magnet I2,

' which causes its armature 4| to be attracted to its pole face 26. Since armature 4| is yieldingly mounted on arm 32 of armature lever 3| it is not essential that arm 32 be adjusted into exact parallelism with pole faces 26, because the armature is free to rock about its one-point mounting and engage both pole faces, even if armature lever arm 32 should happen to be twisted or bowed. As long as armature 4| is held attracted by the selector magnet I 2, the armature lever is held in its extreme counterclockwise position (as viewed in Fig. 1). In this condition of the selector mechanism, bell crank I41 and latching lever I42 are held in their extreme counterclockwise and clockwise positions respectlvely (as viewed in Fig. 3), and stop gate I3I of armature cam '61 is presented toward follower 66, which is out of engagement with cam 51 as a result 01 presentation of armature lever 3| in its counterclockwise position.

Printing telegraph mechanisms of the type for which the selector mechanism herein described isespecially adapted are customarily operated on permutation code combinations of marking and spacing impulses, the former represented by energization of the selector magnet and the latter represented by deenergized condition of the magnet. Each permutation code combination of impulses is preceded by a start impulse which partakes of the nature of a spacing impulse, whereby the selector magnet becomes deenergizecl. When the start impulse is received, the armature lever is restored to its extreme clockwise position by tension spring 6|, and its movement to that position results in (referring to Fig. 3) clockwise rotation of bell crank I41, and counterclockwise rotation of latching lever I42 in oppositionto compression spring I46, whereby the latching shoulder of lever I42 is withdrawn from latching engagement with arm I43 of stop gate I3I. With stop gate I3I unlatched, only its biasing spring (not shown) opposes the torque imparted to cam assembly 58 and its stop arm I32 by shaft 59. The resistance furnished by the biasing spring being relatively insignificant, cam assembly 58 responds to its torque, stop arm I32 escapes from the stop gate I 3| by rocking it, and the cam assembly rotates through one cycle during the reception of a code combination. I

Periodically in timed relation to the signal im- -pulses armature cam 51 rocks armature lever 3| counterclockwise to bring its armature 4| 'into engagement with pole faces 26, and if a marking signal is then applied to the selector magnet, the armature 4| and armature lever 3| will be held in opposition to tension spring 6|. If, instead, a spacing signal is then applied to the selector magnet, the armature lever returns to its extreme clockwise position as soon as its follower portion 66 escapes from an apex of armature cam 61. Thus, under the joint control of armature cam 51 and selector magnet I2, the selective positions of armature lever 3|, cor

responding to successive signal impulses, are de-.

termined. After each selective position is determined, one of the apices of locking cam 16 looks locking bell crank 99 to unlock selector lever 81. When selector lever 81 is unlocked, it responds to any condition of unbalance between springs I03 and I04 resulting from presentation of armature lever 3| in a particular selective position to shift selector lever81 to a corresponding selective position.

The several selector cam projections 11 are arranged with respect to the apices of the locking cam 16 to actuate their associated bell cranks II1 to draw the selector fingers III leftwardly (Fig. 1) afterv the unlocking, selective setting and relocking of selector lever 81. As each selector finger III is drawn leftwardly, one or the other of the depending arms I06 of selector lever 81 is presented in the path of the corresponding abutment I2I of the selector finger. If the selector lever occupies a different selective position than it did at the corresponding instant in the preceding signal combination, an abutment |2I will engage an arm I06 before finger III completes its leftward movement, and in completing such movement, it will be rocked about its disklike portion I I6 to shift its free end to the opposite side of the pivotal mounting I22 of T-levers II2. Upon the restoration of the sword lever III to its extreme right-hand position, it rocks the associated T-lever to a new selective position.

In the manner described in the foregoing paragraph, the several T-levers H2 are positioned permutatively in accordance with a received code signal combination. As each T-lever H2 is positioned in accordance with its code impulse, its associated code disc or code bar (not shown) is positioned permutatively as described in Patent No. 1,745,633 to control the selection of selectable elements.

The leaf spring or spring hinge mountings for the armature lever 31 and the selector lever 81 are employed in substitution for 'the pivots disclosed in Patent No. 1,937,376 granted November 28, 1933, to W. J. Zenner. Frictional pivots may possibly, under some conditions, suffer excessive wear due to friction, with the result that the desired center of pivotal movement of the lever is not maintained. With the torsional pivots afforded by the flat springs, the rapid alternate clockwise and counterclockwise rocking of the levers is devoid of frictional wear upon the supports for those levers.

Brief mention was made in the detailed description of the invention, of the overlapping of the armature supporting arm, and the portion of bracket l3 to which leaf spring hinge 31 is clamped, for the purpose of preventing endwise movement of arm 33 of armature lever 3|. It

with cam 51, spring Bl may tend to rotate lever arm 33 clockwise about the resilient mounting of armature 4| to the extent that flexing of leaf spring hinge 31 would permit. By providing overlapping relation between the armature lever arm 32 and the spring hinge supporting portion of bracket 13, the attracted armature lever arm 32 cannot rock clockwise upon screw 43 because bracket l3 blocks the end of the lever arm to which the spring hinge is connected. Itwill be understood that should different interconnections between .the armature lever and selector lever than centering springs be employed,or should other modifications be made which might result in tendencies of either of the levers to rock in undesired paths, such tendencies may be obviated by introducing positive blocking relation between adjacent members at the point or points of clamping of the spring hinges in accordance with the principle underlying the overlapping of lever arm 32 and bracket I3. I

Although a specific embodiment of the invention has-been disclosed and described herein, it is to be understood that the invention is not limited to such embodiment, but is capable of modification, rearrangement and substitution of parts and elements within the scope of the appended claims.

What is claimed is:

1. In an electroresponsive device, an electromagnet, an armature therefor, a lever arm having an aperture therein, a shouldered screw having the shank extending loosely through said aperture and supporting the armature in fixed relation to said screw, and a compression member loosely supported on the shank of said screw and having arms abutting the lever arm and other arms yieldably and slidably abutting the armature.

2. In an electroresponsive device, an electroture, said compression member having a plurality of sets of arms, means establishing interconnection between one set of arms and said lever arm for preventing rotation of said compression member, and means establishing interconnection between another set of arms and said armature for preventing rotation of said armature upon the axis of said shouldered screw.

3. In an electroresponsive device, an electromagnet, an armature therefor, a cyclically operable lever arm having an aperture therein, a shouldered screw having the shank loosely extending through said aperture and engaging the armature, a resilient compression member loosely supported on the shank of said screw intermediate the lever arm and the armature for absorbing overtravel of said lever arm and irregularities in-alignment and comprising a plurality of sets of arms, one pair of said arms having interconnection with said lever arm, said armature having a plurality of grooves in one face thereof in which the arms of another set are disposed.

4. In an electroresponsive device, a mounting plate, a bracket having a projection pivotally engaging said plate, an electromagnet secured to a portion of said bracket, a block secured to another portion of said bracket, :3. flexible metallic strip having a portion at one end clamped to said bracket by said block, an armature lever clamped to a portion of the other end of said strip, the middle portion of said strip extending across the axis of said pivotal projection, and means for shifting said bracket about said pivotal projection.

5. In an electroresponsive device, a mounting plate, a bracket having a projection pivotally engaging said plate, an electromagnet supported by a portion of said bracket, 9. block supported metallic strip having an end portion secured to the block carried by said bracket, an armature lever clamped to the other end portion of said strip with the end of the armature lever overlapping said block and the middle portion of said strip extending across the axis of said pivotal projection, and means for rocking said bracket about said pivotal projection.

6. In an electroresponsive device, a mounting plate, a bracket having a projection pivotally engaging said mounting plate, an electromagnet supported by said bracket, an armature lever pivoted substantially coaxially with the pivotal engagement of said bracket with said mounting plate, means for rocking said bracket and electromagnet about said projection, an armature carried by said armature lever for universal rocking movement with respect thereto, and yieldable means interposed between said armature lever and said armature for absorbing varia by another portion of said bracket, a flexible ations in alignment and air-gap between said 

